反应详情

温度

140 °C

Another run was conducted according to the process of this invention in the same apparatus employed in the previous runs. The reactor was charged with 5.6 grams (24 mmol) of tungsten oxide (WO3), 4.6 grams (22.5 mmol) of 1,4-dibromo-2-butene, 50 ml of acetic acid, 25 ml of acetic anhydride, and 11.8 grams (218 mmol) of butadiene charged from the vapor phase. The reactor was placed in an oil bath, pressured to 30 psig with oxygen and heated to 140° C. As in the previous runs, the reactor was pressured to 120 psig with oxygen intermittently. The reactor required about 1.25 hours to reach the 140° C. reaction temperature after which the reaction was continued for 6.3 hours. At the end of the reaction period, the reactor was vented and the contents filtered from solid material (3.6 grams) using a small amount of acetic anhydride as the wash liquid. The filtrate was distilled under reduced pressure through an 18 inches Vigreaux column. Two fractions were collected with the first fraction being essentially a mixture of acetic acid and acetic anhydride. The second fraction which weighed 12.3 grams was analyzed by gas-liquid phase chromatography, which revealed that there was obtained 5.4 grams (32 mmol) of 1,2-diacetoxy-3-butene, 0.7 grams (4 mmol) of cis-1,4-diacetoxy-2-butene and 1.5 grams (9 mmol) of trans-1,4-diacetoxy-2-butene for a total yield of 45 mmol of the diacetoxy butenes. This represents a 21 percent yield based on the amount of butadiene charged to the reactor. This result demonstrates that the catalyst system of the instant invention is operable in the absence of the alkali metal compound.

1. additioncharged from the vapor phase
2. customThe reactor was placed in an oil bath
3. customabout 1.25 hours
4. customthe 140° C. reaction temperature after which the reaction
5. customAt the end of the reaction period
6. filtrationthe contents filtered from solid material (3.6 grams)
7. distillationThe filtrate was distilled under reduced pressure through an 18 inches Vigreaux column
8. customTwo fractions were collected with the first fraction
9. additiona mixture of acetic acid and acetic anhydride